questions with new r.o system

hey all, was wondering if anyone has used the ao smith ro system? I purchased and installed this complete ro system for a buddy last night at his house to help him with hard water problems. Im having an issue tho with the ph being higher after the ro system than it was coming from the tap. Anyone have this issue before, should I let the water run for some time to maybe allow some of the water to process a little more....faulty filter? the system does have a remineralizer but i can bypass it from the filter system straight to the faucet just didnt know if maybe this could be adding back in minerals to raise the ph higher than im used to...

edit: ph of the tap water is 7.6
ph of the r.o water is 8.3 to 8.5...just seems rather weird cuz my system is a few years older but didnt have a tank.